Chitosan rod reinforced by self-crosslinking through thermal treatment

Abstract

Chitosan (CS) rods were reinforced at high temperatures to form network structure by self-crosslinking of amino groups. Properties of treated CS rods were studied by FTIR spectroscopy, intrinsic viscosity measurement, mechanical properties testing and water absorption measurement. The FTIR spectra indicated that the CS configuration was transformed from β-CS for untreated CS rods to α-CS for thermally treated CS rods. Meanwhile, the crosslinking also occurred between amino groups of CS. Due to the increase in the crosslinking degree, the intrinsic viscosity increased with the rising of temperature. It was found that the network structure enhanced the bending strength of CS rods, which reached 154.8 MPa when CS rods were treated at 140°C for 2 h. Thermal treatment also reduced the water absorption of CS rods. Due to the improved mechanical properties, thermally treated CS rods could be used as a novel device for internal fixation of bone fracture.